CN1300471A - Impedance-matching device - Google Patents

Impedance-matching device Download PDF

Info

Publication number
CN1300471A
CN1300471A CN99805952A CN99805952A CN1300471A CN 1300471 A CN1300471 A CN 1300471A CN 99805952 A CN99805952 A CN 99805952A CN 99805952 A CN99805952 A CN 99805952A CN 1300471 A CN1300471 A CN 1300471A
Authority
CN
China
Prior art keywords
impedance
matching device
antenna
electric conductor
matching
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN99805952A
Other languages
Chinese (zh)
Other versions
CN1127809C (en
Inventor
E·科伊特萨鲁
L·斯维杰
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Clastres LLC
Telefonaktiebolaget LM Ericsson AB
Original Assignee
Telefonaktiebolaget LM Ericsson AB
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Telefonaktiebolaget LM Ericsson AB filed Critical Telefonaktiebolaget LM Ericsson AB
Publication of CN1300471A publication Critical patent/CN1300471A/en
Application granted granted Critical
Publication of CN1127809C publication Critical patent/CN1127809C/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Images

Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B1/00Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/06Receivers
    • H04B1/16Circuits
    • H04B1/18Input circuits, e.g. for coupling to an antenna or a transmission line
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00Details of, or arrangements associated with, antennas
    • H01Q1/12Supports; Mounting means
    • H01Q1/22Supports; Mounting means by structural association with other equipment or articles
    • H01Q1/24Supports; Mounting means by structural association with other equipment or articles with receiving set
    • H01Q1/241Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM
    • H01Q1/242Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM specially adapted for hand-held use
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q19/00Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic
    • H01Q19/06Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using refracting or diffracting devices, e.g. lens
    • H01Q19/09Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using refracting or diffracting devices, e.g. lens wherein the primary active element is coated with or embedded in a dielectric or magnetic material

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Details Of Aerials (AREA)
  • Variable-Direction Aerials And Aerial Arrays (AREA)
  • Input Circuits Of Receivers And Coupling Of Receivers And Audio Equipment (AREA)

Abstract

The present invention relates to an impedance-matching device of antenna units, and in particular to antenna-matching in small radio units. An impedance-matching device is arranged in a radio equipment having an antenna, between said antenna and a feeding unit, e.g. an output power unit, the impedance quotient of which units exceeding a factor 3. The invented impedance-matching includes at least two quarter-wave transformers connected in series, which consist of a dielectric material having a dielectric coefficient, the value of which is exceeding a factor 10. The device may be made with dimensions so small that it may be integrated with the antenna to an antenna unit and despite the small dimensions, good frequency characteristics are achieved, such as good precision, easy tuning and sufficiently broad bandwidth.

Description

Impedance-matching device
Technical field of the present invention
The present invention relates to the impedance matching of antenna element, specifically, relate to the coupling of the antenna in the micro radio electric unit.
Background of the present invention
Radio unit is equiped with small size antenna sometimes especially for the micro radio electric unit of mobile wireless communication.This is meaning the center of radiation and is being positioned at position near user's ear from the shell of the strongest radiation field of antenna and this radio unit.In order to address this problem, wish the center of radiation ear rising certain distance by the user.
Knew before that if radio unit is equipped with a half-wave doublet antenna, the axis of described radiation field will be positioned at the center of antenna.As a result,, will remove radiation field by ear, and will obviously reduce near user's the ear and the position radiation field intensity of head by making the antenna long enough.
The shortcoming relevant with the high impedance input dipole antenna of half-wave doublet antenna and other type is that they are difficult to realize impedance matching, if be like this when particularly wanting to make antenna to cover two or more humorous wavestrips.For example, if import at its half-wave doublet antenna one to one at two ends, this requirement has very high input impedance, is 800 ohm magnitude.If the core electrode couple antenna at it is imported, input impedance will obviously reduce, and be 70 ohm magnitude.The antenna of small-sized radio unit is as a ruler that is stretched out by its one of end.Simultaneously, the power stage that antenna is imported is provided with much lower impedance, is 50 ohm magnitude.In order to prevent reflection and poor efficiency to occur, make the high input impedance coupling of the low output impedance and the antenna of power stage.This requirement has an impedance-matching device, realizes coupling between antenna and power stage.This impedance-matching device also can be called as the impedance device, or is called impedance more tout court, impedance matching, or only be called coupling.
Before known dissimilar impedance-matching devices.A kind of coalignment of previously known is the transformer that has resonance circuit.On principle, a major part is relevant with the output of power stage, and sub section comprises tunable resonance circuit, and is relevant with antenna.This resonance circuit comprises a parallel coil and an electric capacity.This coil can be provided with an air-core sometimes.In a kind of modification of resonance circuit, core is made by the fillet line, and this is meaning produces the printed substrate pattern, to form this coil.In another modification, saved main winding, the conductor of power stage is directly connected to any suitable position of secondary winding.This solution has a plurality of advantages, and is less and less such as parts, and not only compares with main winding but also with the transformer of secondary winding, saved space and cost like this.A significant disadvantages relevant with this solution is its narrow bandwidth.
The impedance-matching device of another kind of type comprises the use helical resonator, and in fact, it is a filter part, and under extreme case, its function is as a tunable oscillation circuit.
Yet, in mini-plant, during for example the movable wireless Denso is equipped with, have only very little space to be used for impedance-matching device.
Brief summary of the invention
In order to prevent reflection and to overcome poor efficiency, must make the output impedance of power stage and the input impedance matching of antenna.
No matter power stage/input stage is provided with the obviously high or obviously low output impedance than the input impedance of input stage, all will need coupling.The ratio of the highest and minimum impedance is the impedance ratio I.Therefore, high impedance ratio is meaning big difference between input impedance and output impedance.It is complicated that the impedance-matching device of previously known usually requires very big space and/or their design.Yet, in mini-plant is equipped with such as the movable wireless Denso, only provide a little space for impedance-matching device.
The present invention has provided a solution for resistance matching problem, promptly realizes the impedance matching of antenna in little space with short distance.
Another problem that the present invention solves is to have obtained enough bandwidth by this impedance-matching device.
Another problem that the present invention solves is that impedance-matching device be simple and cheap for making.
An object of the present invention is to provide a kind of impedance-matching device in the length of strictness restriction, and still precision and bandwidth are kept high requirement, and device of the present invention be simple and cheap for making.
Speak briefly, the solution that is proposed comprises by means of the quarter-wave transformer and mating in several ladders.
Say that in more detail stacked the quarter-wave transformer in this solution, its dielectric material surpasses a kind of material of 10 by the value of dielectric coefficient ε and constitutes.
This scheme by dealing with problems has obtained many benefits.Can make this impedance-matching device enough for a short time, thereby even feasible antenna is integrated in identical housing mutually with this coalignment become possibility.This device is suitable for coupling part between loop/module-grade and has using in the radio equipment of high impedance ratio (I>3) especially.Will be clear by following description, impedance-matching device is simple for making, is made of considerably less parts, and also is cheap for making therefore.Let it be to the greatest extent, and size is little, and still, it provides good frequency characteristic, and is tuning easily such as good precision, and has enough bandwidth.Designer and producer can not be subjected to adopting the troubling of shortcoming of loop and coil, because these loop elements are difficult to strictly make, therefore bring serious loss.
Now will be in more detail by means of example of the present invention and the present invention is described with reference to the drawings.
Brief description of the drawings
Fig. 1 shows a movable wireless electric unit, and it has first embodiment of the impedance-matching device that is integrated in this antenna element;
Fig. 2 shows first embodiment of impedance-matching device with section;
Fig. 3 is the view of first embodiment of impedance-matching device;
Fig. 4 is the perspective view of first embodiment of impedance-matching device;
Fig. 5 is the perspective view of second embodiment of impedance-matching device;
Fig. 6 shows second embodiment of impedance-matching device with section;
Fig. 7 is a characteristic curve, and how it influences bandwidth if showing dissimilar impedance-matching devices.
The description of preferred embodiment
Fig. 1 shows a movable wireless electric unit 10, and it has an integrated antenna element 12, in the drawings this cell mesh cut open.This antenna element is made up of antenna 14 and an impedance-matching device 16.Antenna 14 can at one end be imported it with radio wave for the half-wave doublet antenna of the sort of type.Its input impedance is the magnitude of 800 ohm (0.5-1 kilo-ohms).It is the output impedance of 50-100 ohm that the output stage of radio unit has magnitude.In order to make this big difference in the impedance realize coupling, between output stage and antenna, be connected an impedance-matching device.Because this impedance-matching device is small-sized, it and antenna is integrated into an antenna element.
Imagination is to realize coupling with the form of ladder by a plurality of quarter-wave transformers that in series are coupled, and these transformers are made by a kind of dielectric material, and this material has high dielectric coefficient, still, between electric conductor and the interior electric conductor different distances is arranged outside.
Referring now to Fig. 2 impedance-matching device is described in more detail.The figure shows the longitudinal profile of first embodiment of this device.In this embodiment, impedance-matching device 16 comprises four quarter-wave transformer 18-24, between the input stage of radio unit 10 and antenna 14 they is connected in series.These transformers are coaxial type.Each quarter-wave transformer 18-24 comprises an outer electric conductor 26, also it is called screen, and it is made by a kind of electric conducting material.Medial surface near this screen is a kind of dielectric material 28, and it is the material to electric insulation.Outer electric conductor and dielectric material are wrapping interior electric conductor 30.Dielectric material 28 is full of the space between electric conductor 26 and 30.Every kind of dielectric material has its dielectric coefficient ε.
As seen from the figure, interior electric conductor 30 is made a shell, that is, electric conductor is a tubulose.This can be implemented to enough thickness by the inboard coating metal at dielectric material.It is not uniform that this solution is meaning the quarter-wave transformer.The design of shell is favourable for weight.In addition, electric conductor 30 can be uniformly, still, also heavier weight will be arranged.In small-sized mobile wireless electric unit, wish weight and dimensional parameters are reduced to minimum.Coalignment has a high impedance end/weak point side 34 and a low-impedance end/weak point side 32.The saying of " high impedance " is a relative notion, is that this end of finger device has the impedance more higher than low-impedance end.High impedance end is connected on input or the output, and this end has higher impedance with respect to another input or output.
By changing the distance between outer electric conductor 26 and the interior electric conductor 30, and, also can change the impedance of quarter-wave transformer by changing the thickness of the dielectric material 28 between them.Distance between the electric conductor is big more, and impedance is high more.Further the possibility that changes is to change material and change dielectric coefficient.
In the embodiment that proposes according to Fig. 2, to center line identical distance is arranged with the different outer electric conductor 26 of the quarter-wave transformer 18-24 that is connected in series, the outer electric conductor 26 of impedance-matching device 16 also is positioned at and leaves the identical distance of center line 36.Because outer in this case electric conductor 26 is a tubulose, its cross section is made up of circular arc, and distance equals radius R, and radius is fixed.Interior electric conductor 26 is made the tubulose of ladder, still,, change to the ground, range step of center line 36 for each new quarter-wave transformer.Because the radius r of interior electric conductor being reduced by the power stage/input stage of radio unit ladder ground to the path of the installation of antenna 14, also makes the raising of impedance step ground for each quarter-wave transformer.
If use dielectric coefficient ε is at least 80 material, each quarter-wave transformer stage (18-24) for example can be 9 millimeters under 900MHz.If realize coupling with the quadravalence section, the overall size of coalignment may be 36 millimeters high.The rigidity control that the diameter of coalignment is mainly possessed by described design.Because the diameter of interior electric conductor 30 (antenna connection) is fixed with the relation of the diameter of outer electric conductor 26 (screen), have nothing to do to a great extent with the size of selecting coalignment, as long as described relation is fix just passable.Yet, can not select too little diameter (being 0.01 millimeter magnitude) for interior electric conductor, this is because ohmic loss increases along with reducing of diameter.The lower acceptable ohmic loss of electric conductor in diameter is 0.5 millimeter copper electric conductor, can obtaining.
The solution of this proposition is for being very significant up to 2GHz.In the frequency band of 1.8GHz, each transformer ladder will have only 4.5 millimeters long.Frequency more than 2GHz, because different, other impedance-matching device may be significant.
By the constant other shape that has obtained coalignment of distance between electric conductor 30 in keeping and the center line 36, this is meaning for the distance/radius between each quarter-wave transformer stage 18-24 ladder ground change center line 36 and the outer electric conductor 26.
Fig. 3 shows first embodiment of this coalignment when the low-impedance impedance end 32 in the two ends of impedance-matching device 16 is turned to the observer.By the outside to interior to the center, at first be outer electric conductor 26, be dielectric material 28 and interior electric conductor 30 then, they are parts that the quarter-wave transformer ladder 18 of lowest impedance is arranged.After ladder 18, what follow is the other transformer stage 20,22 and 24.Each transformer ladder is one 1/4th ladder, and length is 1/4th of electromagnetic wavelength.It between each ladder transition region 19,21 and 23.
Fig. 4 is the cutaway view of first embodiment, and the finite region of four transformer ladders and their inside is shown in broken lines in the drawings.Can be integrated in a tensile antenna in the coalignment 16, thereby this antenna is installed in the centre bore 38, in high impedance ladder 24, form this hole.In the insertion position, the chamber that the utmost point of antenna passes coalignment stretches, and this chamber forms in the mid portion of interior electric conductor 28.
Fig. 5 and 6 shows second embodiment of impedance-matching device 16.This embodiment is different with first embodiment to be: the distance between electric conductor and interior electric conductor 26 and 30 is respectively a continually varying outside, rather than step-like.In other words, the transition region between ladder has been made into a continuous transition region.
Fig. 5 is the perspective view of impedance-matching device 16, wherein, with the dotted line inner finite region of drawing, promptly in the inner region of electric conductor 30.The space of sky in the centre of device is conical.In addition, outer electric conductor 26 can be determined a circular cone volume, and interior electric conductor 30 has a fixing radius.
This illustrates the section of second embodiment of impedance-matching device 16.In this case, the side/end 34 is respectively a straight line to the radial distance between the interior and outer electric conductor 26 and 30 to the high impedance weak point by the short side of Low ESR/end 32.This distance is relevant with the output impedance that in the thickness of the end place of device dielectric material and lower impedance in two impedances will mating is power stage, therefore, this thickness is than being connected to high impedance, and for example the thickness of that end of the impedance of the antenna side of described device is little.Interior electric conductor and outside between the electric conductor radially changing of distance also can be non-rectilinear, in this is meaning the radius of electric conductor and/or outer electric conductor on the longitudinal direction of coalignment by end 32 34 variations non-linearly to the end.
Good characteristics of these parts are that it has high efficiency, the Q factor that does not promptly load or so-called quality factor height.Under the situation that impedance matching occurs with the form of a ladder, obtain the high Q factor that does not load, numerical value is 16 (800 ohm of input impedance and output impedance 50 ohm between ratio).On the contrary, if realize coupling, obtain the low Q factor that loads with several ladders.In first embodiment, to realize coupling in four ladders, the impedance of each ladder doubles (by 50 ohm to 800 ohm), and this is meaning the Q factor that loads will be 8=4 (ladder number) * 2 (the Q factor/ladder number).Therefore, compare with realize the factor of impedance matching with a ladder, the Q factor has been reduced to half.
The coupling that realizes with a big ladder is meaning this solution will narrow bandwidth, and the solution of the coupling that realizes with several ladders has realized the coupling of broader bandwidth.The number of transformer ladder is by the desirable bandwidth decision to system.Fig. 7 shows characteristic curve, and how frequency curve changed when expression realized coupling with a ladder or several ladder.The curve H1 that draws with dotted line represents the loss relevant with the coupling of a ladder.The maximum of curve is in the centre frequency of 900MHz.Optimum Match (100%) is meaning in centre frequency does not have impedance loss.Along with the increase of the distance of leaving centre frequency, match penalties promptly increases.Curve and-frequency between the point that the 3dB line intersects measures bandwidth.Single ladder coupling (H1) has narrow bandwidth B 1.The curve Hn that draws with continuous lines represents the loss relevant with the coupling of several ladders.In decay place of-3dB, bandwidth B n is wideer than single ladder situation significantly.In the mobile wireless electricity was used, importantly, it is wide to making RX and TX frequency band respectively significantly in the bandwidth of coalignment that bandwidth is wanted.
The coalignment that is proposed can combine with dissimilar antennas.Like this, this device will not be confined to half-wave doublet antenna.Do not have hell and high water with the equipped collapsible antenna of the remodeling of this device.
Impedance-matching device 16 can be made of very simple method.Be molded to dielectric material with mould, this is meaning under high pressure and high temperature this device is being made one.A suitable selection that is used for the material of molding is a ceramic material.Ceramic post sintering is become non electrically conductive material, and it looks and looks like glass.Ceramic material is the mixture of salt of the metal oxide of barium, manganese, cobalt etc.In moulding process, produce the dielectric material of high-dielectric coefficient (ε=10).The different component of metal oxide produces the new ceramic material that the different dielectric coefficient is arranged.With metal cover, the wall of the final parts of coating or spraying dielectric material, perhaps additionally final parts are immersed in the metal bath.Subsequently, the metal of curing forms outer and inner electric conductor.Depend on and wish what requirement can be made into interior electric conductor uniformly or hollow.
For the use in small-sized radio unit, in the past, the quarter-wave transformer was without any special interest.Design of the present invention is meaning and can produce impedance-matching device with enough little size, and is meaningful for the application in small-sized radio unit.Dielectric coefficient ε surpass 10 material for example ceramic material be the design's vitals.Can be included in multiple different radio equipments neutralization to coalignment of the present invention and be used for radio communication device.The example of such device is a terminal and be used for the femto cell that mobile wireless is communicated by letter, and the example of such device can also be the GPS equipment, such as satellite receiver.
Certainly, the invention is not restricted to embodiment described above and that illustrate in the drawings, and can in the scope of appending claims, change.

Claims (8)

1. an impedance-matching device (16), it is arranged on a kind of antenna (12) in the radio equipment (10) and feed-in unit of being included in for example between power output unit, the impedance ratio of these unit surpasses 3, it is characterized in that, this impedance-matching device (16) comprises at least two quarter-wave transformers that are connected in series (18,20), they are that a kind of dielectric material (28) of ε is made by dielectric coefficient, and the value of ε surpasses 10.
2. according to the impedance-matching device described in the claim 1, it is characterized in that,, and constitute the outer electric conductor and the interior electric conductor of described device (16) respectively the outer wall of dielectric material (28) and inwall (being respectively 26 and 30) metallization.
3. according to the impedance-matching device described in the claim 2, it is characterized in that impedance-matching device comprises at least two coaxial quarter-wave transformers, between its outer wall and inwall (26,30), different distances is arranged.
4. according to described impedance-matching device one of among the claim 1-3, it is characterized in that interior electric conductor is a hollow.
5. according to described impedance-matching device one of among the claim 1-4, it is characterized in that the radius of interior electric conductor is different for each new quarter-wave transformer ladder.
6. according to described impedance-matching device one of among the claim 1-4, it is characterized in that interior electric conductor is a hollow, and between each transformer ladder, be provided with an all even continuous transition region, its feature also is, changes continuously at a ladder inside radius.
7. according to described impedance-matching device one of among the claim 1-6, it is characterized in that this impedance-matching device and antenna (14) form as one, thereby constitute an antenna element (12).
8. according to described impedance-matching device one of among the claim 1-7, it is characterized in that, comprise this impedance-matching device at the equipment that is used for radio communication.
CN99805952A 1998-05-08 1999-04-23 Impedance-matching device Expired - Fee Related CN1127809C (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
SE9801611A SE512036C2 (en) 1998-05-08 1998-05-08 Device for impedance matching comprising two serial quartz wave transformers
SE98016116 1998-05-08
SE9801611-6 1998-05-08

Publications (2)

Publication Number Publication Date
CN1300471A true CN1300471A (en) 2001-06-20
CN1127809C CN1127809C (en) 2003-11-12

Family

ID=20411232

Family Applications (1)

Application Number Title Priority Date Filing Date
CN99805952A Expired - Fee Related CN1127809C (en) 1998-05-08 1999-04-23 Impedance-matching device

Country Status (12)

Country Link
US (2) US6222500B1 (en)
EP (1) EP1097489A2 (en)
JP (1) JP2002515660A (en)
KR (1) KR100554634B1 (en)
CN (1) CN1127809C (en)
AU (1) AU762645B2 (en)
BR (1) BR9910280A (en)
EE (1) EE03890B1 (en)
HK (1) HK1038285A1 (en)
MY (1) MY121068A (en)
SE (1) SE512036C2 (en)
WO (1) WO1999059220A2 (en)

Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7746292B2 (en) 2001-04-11 2010-06-29 Kyocera Wireless Corp. Reconfigurable radiation desensitivity bracket systems and methods
JP2003188605A (en) * 2001-12-18 2003-07-04 Murata Mfg Co Ltd Low-pass filter
US7180467B2 (en) * 2002-02-12 2007-02-20 Kyocera Wireless Corp. System and method for dual-band antenna matching
US6856211B2 (en) * 2002-05-21 2005-02-15 Nagano Japan Radio Co., Ltd. Coaxial type impedance matching device
US7720443B2 (en) 2003-06-02 2010-05-18 Kyocera Wireless Corp. System and method for filtering time division multiple access telephone communications
US7366304B2 (en) * 2003-10-07 2008-04-29 Lenovo (Singapore) Pte. Ltd. Cruable U-NII wireless radio with secure, integral antenna connection via SM BIOS in U-NII wireless ready device
JP4469632B2 (en) * 2004-02-24 2010-05-26 富士通株式会社 Control device for antenna matching circuit
US7453393B2 (en) * 2005-01-18 2008-11-18 Siemens Milltronics Process Instruments Inc. Coupler with waveguide transition for an antenna in a radar-based level measurement system
KR20080064839A (en) * 2005-09-23 2008-07-09 캘리포니아 인스티튜트 오브 테크놀로지 Electricl funnel: a novel broadband signal combining method
US8723722B2 (en) 2008-08-28 2014-05-13 Alliant Techsystems Inc. Composites for antennas and other applications
US7922528B2 (en) * 2009-04-03 2011-04-12 John Mezzalingua Associates, Inc. Connector and connector system with removable tuning insulator for impedance matching
TWI462385B (en) * 2009-05-26 2014-11-21 Wistron Neweb Corp Self-matching band-pass filter and related frequency down converter
US10813691B2 (en) * 2014-10-01 2020-10-27 Covidien Lp Miniaturized microwave ablation assembly
CN116130912B (en) * 2023-04-17 2023-06-13 中国科学院合肥物质科学研究院 Power transmission system

Family Cites Families (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB591667A (en) * 1942-03-31 1947-08-25 Sperry Gyroscope Co Inc Improvements in or relating to impedance transformers for wave guides
US2518665A (en) * 1942-08-22 1950-08-15 Emi Ltd Connector for high-frequency transmission lines and the like
US2438915A (en) * 1943-07-30 1948-04-06 Sperry Corp High-frequency terminating impedance
NL69844C (en) * 1944-11-16
US2767380A (en) * 1952-09-30 1956-10-16 Bell Telephone Labor Inc Impedance transformer
DE1122116B (en) * 1960-07-07 1962-01-18 Rohde & Schwarz Connection piece between coaxial lines
US3157845A (en) * 1963-01-29 1964-11-17 Gen Electric Rectangular to ridged waveguide transition having separate mode converting and impedance matching sections
US3909755A (en) * 1974-07-18 1975-09-30 Us Army Low pass microwave filter
FR2447111A1 (en) * 1978-07-11 1980-08-14 Radiotechnique Compelec BROADBAND MICROWAVE OSCILLATOR, WITH GUNN DIODE, GRANTED BY A GARNET
JPS58196701A (en) * 1982-05-11 1983-11-16 Nec Corp Microwave circuit
US4617539A (en) * 1985-05-13 1986-10-14 Raytheon Company Reflective phase shifter
US4694264A (en) * 1986-03-05 1987-09-15 The United States Of America As Represented By The United States Department Of Energy Radio frequency coaxial feedthrough device
US4760400A (en) * 1986-07-15 1988-07-26 Canadian Marconi Company Sandwich-wire antenna
US4847629A (en) * 1988-08-03 1989-07-11 Alliance Research Corporation Retractable cellular antenna
US5065819A (en) * 1990-03-09 1991-11-19 Kai Technologies Electromagnetic apparatus and method for in situ heating and recovery of organic and inorganic materials
US5369367A (en) * 1992-12-02 1994-11-29 Hughes Aircraft Company Wideband coax-to-TM01 converter and testing system using the same
US5563615A (en) * 1993-01-15 1996-10-08 Motorola, Inc. Broadband end fed dipole antenna with a double resonant transformer
JP2821567B2 (en) * 1993-02-26 1998-11-05 五郎 菅原 High frequency signal transmission equipment
SE9600538D0 (en) * 1996-02-13 1996-02-13 Allgon Ab Dual band antenna means incorporating helical and elongated radiating structures
US5847625A (en) * 1997-04-02 1998-12-08 Tx Rx Systems Inc. Power Divider directional coupler

Also Published As

Publication number Publication date
AU762645B2 (en) 2003-07-03
US20010026243A1 (en) 2001-10-04
SE9801611D0 (en) 1998-05-08
SE9801611L (en) 1999-11-09
EE200000635A (en) 2002-04-15
EP1097489A2 (en) 2001-05-09
MY121068A (en) 2005-12-30
BR9910280A (en) 2001-01-09
KR20010071219A (en) 2001-07-28
JP2002515660A (en) 2002-05-28
WO1999059220A3 (en) 2000-01-20
KR100554634B1 (en) 2006-02-22
SE512036C2 (en) 2000-01-17
HK1038285A1 (en) 2002-03-08
WO1999059220A2 (en) 1999-11-18
EE03890B1 (en) 2002-10-15
CN1127809C (en) 2003-11-12
US6222500B1 (en) 2001-04-24
AU4401399A (en) 1999-11-29

Similar Documents

Publication Publication Date Title
CN1127809C (en) Impedance-matching device
US6650303B2 (en) Ceramic chip antenna
KR100384656B1 (en) Dual-band helix antenna with parasitic element
US20060232493A1 (en) Circular-polarization dipole helical antenna
CN1768450A (en) Dielectrically-loaded antenna
KR20020013977A (en) Dual band patch antenna
CN101043099A (en) Loop antenna with at least two resonant frequencies
US4890116A (en) Low profile, broad band monopole antenna
EP0772255B1 (en) Multiband antenna with a distributed-constant dielectric resonant circuit, and multiband portable radio apparatus comprising such an antenna
WO2014134149A1 (en) Dipole antenna assembly having an electrical conductor extending through tubular segments and related methods
US7876280B2 (en) Frequency control of electrical length for bicone antennas
CN1244956A (en) Dual band antenna
US6288681B1 (en) Dual-band antenna for mobile telecommunication units
US6525692B2 (en) Dual-band antenna for mobile telecommunication units
KR101859179B1 (en) Compact, wideband log-periodic dipole array antenna
US4958164A (en) Low profile, broad band monopole antenna
AU734637B2 (en) Telescopic antenna assembly
US6016431A (en) Radiotelephones with integrated matching antenna systems
CN1298079C (en) Double frequency band antenna for mobile communication unit
EP1938422A1 (en) Multi-band antenna
US4439772A (en) Inductor type half wave antenna
KR101816018B1 (en) Compact, wideband log-periodic dipole array antenna
RU2769306C1 (en) Broadband antenna
WO2003030302A1 (en) Helical antenna
EP0650214B1 (en) Antenna and cordless telecommunication apparatus comprising an antenna

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant
ASS Succession or assignment of patent right

Owner name: AOPU DISI CELLULAR TECHNOLOGY CO., LTD.

Free format text: FORMER OWNER: CLUSTER CO., LTD.

Effective date: 20150122

Owner name: CLUSTER CO., LTD.

Free format text: FORMER OWNER: TELEFONAKTIEBOLAGET LM ERICSSON (SE) S-126 25 STOCKHOLM, SWEDEN

Effective date: 20150122

C41 Transfer of patent application or patent right or utility model
TR01 Transfer of patent right

Effective date of registration: 20150122

Address after: Texas, USA

Patentee after: Telefonaktiebolaget LM Ericsson (publ)

Address before: Delaware

Patentee before: Clastres LLC

Effective date of registration: 20150122

Address after: Delaware

Patentee after: Clastres LLC

Address before: Stockholm

Patentee before: Telefonaktiebolaget LM Ericsson

CF01 Termination of patent right due to non-payment of annual fee
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20031112

Termination date: 20180423